Right before we went on vacation, I bought a set of these Fisher Price Stack and Roll Cups, thinking they'd be a nice way to entertain our two little guys while in the rental house. They didn't disappoint, and in fact they even gained the attention of everyone older than the two littlest.

The cups nest into one another when inverted, click and stack together when right side up, can be rearranged, filled with little items, counted, and rolled. At such a reasonable price, they've been a winner here, and they get used every single day.